Conventionally, there is known development of an electric brake apparatus in which an electric motor is rotationally driven depending on the amount of stepping of a brake pedal to generate braking force using the rotational torque of the electric motor. For example, the electric brake apparatus proposed in JP-A-2001-32868 comprises an actuator having an electric motor, and is adapted to apply braking force to a wheel by pressing a brake pad against a disc rotor depending on the amount of stepping of a brake pedal.
The electric brake apparatus in the above conventional example uses the position of the brake pad at the time of releasing thrust detected by a thrust sensor when braking is finished as a braking start position; controls a gap between the brake rotor and the brake pad (hereinafter referred to as a pad gap) so that the brake pad is spaced from the braking start position by a predetermined amount when the brake is released; and controls the thrust of a piston depending on the thrust detected by the thrust sensor when generating the braking force.
When the brake is released, in order to avoid contact between the disc rotor and the brake pad (dragging of the brake) resulting from thermal deformation of the disc rotor, the temperature of the disc rotor or the temperature of the brake pad (hereinafter referred to as pad temperature) is detected by a temperature sensor, or the temperature of the disc rotor is estimated based on the cumulative value of heat energy of the disc rotor calculated based on the vehicle speed, the outside air temperature and a braking state, so that the brake pad is spaced from the disc rotor depending on the amount of thermal deformation of the disc rotor.